The present invention relates to a winding apparatus for flexible sheet-like arrangements, in particular printed products such as newspapers, periodicals and parts thereof, according to the preamble of claim 1.
A winding apparatus of this type is disclosed in EP-A-0 652 176 and in the corresponding U.S. Pat. No. 5,622,027. It has a winding core, which is mounted rotatably in a framework and can be driven by a drive shaft, and a winding band, which directs the flexible sheet-like arrangements essentially tangentially onto the winding core and is wound up onto the winding core together with the sheet-like arrangement. A drive train comprising a driving pulley, a drive belt and a drive belt pulley makes it possible for the rotary shaft, on which the winding core is mounted in a rotatable manner, to be rotated by the same drive motor as a band reel, from which the winding band is unwound during the winding up onto the winding core. Located between the winding core and the rotary shaft is a helical spring which is fastened, at one end, to the winding core and, at its other end, to the rotary shaft. The arrangement is such that the ends of the spring can move relative to one another in order to change the stressing state of the spring. The apparatus thus makes it possible for the torque to which the winding core is subjected to be adapted to the increasing roll diameter as the winding band is wound up onto the winding core together with the sheet-like arrangements, regulation not being necessary.
In a further winding apparatus for flexible sheet-like arrangements which is disclosed in EP-A-0 719 720 and in the corresponding U.S. Pat. No. 5,673,869, the roll rests circumferentially on endless supporting belts which can be driven by means of a drive motor. The band reel is connected in a rotationally fixed manner to a drive wheel. During operation, said band reel has a drive belt engaging around it, the drive belt, for its part, being driven by the drive motor. The drive belt and the drive wheel form a friction or slip clutch.
In a further winding apparatus known from CH-A-652 699 and the corresponding U.S. Pat. No. 4,587,790, the winding core and the band reel are arranged on a mobile framework. The latter can be attached alternately to a stationary winding-up station and unwinding station. The framework has a jaw brake in each case for the winding core and for the band reel. On the winding-up station, the winding core is connected to a drive motor of the winding-up station via an angular gear mechanism. During the winding up of the sheet-like arrangements onto the winding core, the jaw brake assigned to the band reel remains active in order to produce the necessary tensile stressing in the winding band. In the unwinding station, on the other hand, the band reel is driven by the drive motor via an angular gear mechanism, in which case the jaw brake assigned to the winding core remains active.
EP-A-0 243 837 and U.S. Pat. Nos. 4,768,768 and 4,928,899 disclose a winding apparatus in which the roll and the band reel are driven by the same drive motor. The latter drives frictional wheels which interact with the winding band on the circumference of the roll and on the circumference of the band reel.
It is an object of the present invention to provide a winding apparatus of the generic type which is of particularly straightforward construction.
This object is achieved by a winding apparatus which has the features of claim 1.
Frictionally locking connections are of particularly straightforward construction and allow coupling between the driving and the driven parts in an extremely straightforward manner. As the winding band is wound up onto the winding core together with the sheet-like arrangements, the drive part of the frictionally locking connection runs more quickly than the winding-core part, as a result of which the winding core, on account of the frictional locking, is subjected to a certain torque in the winding-up direction and, at the same time, the winding band is retained under tensile stressing. The same applies to the unwinding of the winding band from the unwinding core together with the sheet-like arrangements. In this case, the band reel is driven at a greater circumferential speed than the winding core. Both during the winding-up operation and during the unwinding operation, the winding core slips in relation to the part driving it.
Further preferred embodiments of the winding apparatus are specified in the dependent claims.